This is the Atelier Tsubasa original trumpet mouthpiece "3CS". I am selling it because I am changing sizes. This is a Bach 3C size mouthpiece, a standard for all-genre mouthpieces. It was created to achieve "smooth playability," "smooth transitions across all registers," "good responsiveness," and "maximum sound efficiency with minimal effort." ~Specifications~ ・Rim The semi-flat shape of the "MV 1-1/2C" made by Mr. Kameyama, which is loved by players around the world, regardless of professional or amateur status, is maintained, with the inner diameter adjusted to the 3C size. This shape provides both stability and control. ・Cup The depth of a modern 3C, producing a bright and brilliant tone. ・Throat #26 ・Backbore Bach Mount Vernon